Refrigerating apparatus.



L. K. DOELLING.

'REFRIGEBATING APPARATUS. APPLICATION 1111111) 1 23.29, 1911.

' 1,106,287. Patented Aug. 4, 1911 COMPRESSOR CONDENSER STORAGE TANK Q/Vf so: I I LEI-c 1'0: 1 1103 c I 11 11 11 LOUIS K. DOELLING, OF NEW ROCHELLE, NEW YORK.

REFRIGERATING APPARATUS.

Specification of Letters Patent.

Application filed February 28, 1911.

Patented Aug. 4, 1914. Serial No. 611,528.

To all whom, it may concern Be it known that I, LOUIS K. DonLLrNo, a citizen of the German Empire, residing in New Rochelle, county of \Vestchester, btate of New York, have invented certain new and useful Improvements in Refrigerating Apparatus, described in the following speci fication.

The improvements constituting the invention are particularly concerned with the control and the regulation of flow of the liquid refrigerant in artificial refrigerating systems of the compression and absorption types, and its object is to simplify and reduce the manipulation necessary for maintaining the freezing coils or other expansion device of such systems in efficient normal operation, and more especially to eliminate the functions of the so-called expansion valve, by providing in place thereof an arrangement of parts whereby a sufiieient and suitable working control of such systems can be accomplished by regulation merely of the speed of the engine or the temperature of r the condenser or absorber.

Other objects and results of the invention will be a parent to those familiar with this subject, rom the following description and from the drawing forming part of this specification.

The drawing illustrates in diagram the best and simplest form in which I have thus far contemplated using the principle of my invention, but such principle is susceptible of embodiment in various different ways and with various different kinds of apparatus, as will be readily understood, according to the character of the system in which used and the preference of the epgineer.

I have taken a compression system for illustration in the drawings. The compressor, such as usual or suitable for compression systems, is indicated at 1, the condensing apparatus therefor at 2. and a storage tank for the accumulated liquid at 3.

The liquid from the storage tank flows by the ipe 4 to a coil 18, indicated by dotted lines, and thence by pipe 4 to the liquid admission valve 5, by which it enters an inclosed pre-separator receptacle or reservoir 6. The valve 5 is controlled by a float 7 mounted on the end of a lever pivoted at 8 to the interiorof the tank and linked to the stem of the valve, the arrangement of valve and leverage being preferably about as indicated diagrammatically in the drawing so that the rising liquid in the tank will automatically close the valve on its seat and shut off the supply of liquid when the latter reaches a definite or predetermined level. A type of valve which is not readily moved by the pressure of the liquid behind it, is obviously desirable and such a valve should obviously be connected with the float-lever as near to the fulcrum of the latter as consistent with the necessary amplitude of valve movement, so that the load on the float will be as light as possible and also substantially constant, thereby rendering the valve independent of variations in the pressure of the liquid behind it. The operation of the float-controlled valve, as Will be readily seen, determines a rate of ,liquid supply to the reservoir (3 which is necessarily substantially equal to the rate of outflow therefrom, and any other form of device capable of performing a like function can be used in place of the specific means for this purpose shown in the draw ing. The refrigerant in the case in hand may be regarded as ammonia and as it passes through the pipe 4 to valve may be under considerable pressure relatively to the suction pressure. In reservoir (5 its pressure and temperature mutually adjust themselves with formation of an overlying body of gas and an underlying body of liquid. From the reservoir 6 a liquid outlet pipe 9 conducts the liquid ammonia at reservoir temperature and pressure to the refrigerating coil 10 or such device or means as may be used for the evaporation of the liquid refrigerant. Preferably the outlet pipe leads horizontally to the bottom loop or loops of an upright expansion coil, the greater part of which is disposed above the level of the liquid ammonia in the reservoir, and so that the lowest loop of the coil is thus maintained substantially flooded. The upper terminal loop of the coil leads to a separator 11, which may be made according to any suitable design that will permit separation of liquid and gas and prevent liquid refrigerant from passing from the coil into the main suction-line and thence to thecompressor. The suction line is marked 12 in the drawing. The separator is also preferably disposed above the level of the liquid in the reservoir (3 so that the separated liquid therein may drain by gravity through the drain-pipe 13 back to the reservoir. where it will of course be returned through the coil,

and preferably the drain-pipe enters the reservoir below the liquid level therein. In cases where the separator is not conveniently located above the tank, other means for returning and using the separated liquid may be resorted to, but by utilizing gravity for this purpose the return of the liquid may be continuous and is accomplished without additional consumption of power, or loss by evaporation.

In the apparatus thus far described, it will be observed that the liquid in the reservoir (3 flows into and upwardly in the refrigerating coil wherein it is evaporated by the heat taken from the material to be cooled, and the expanded refrigerant, a mixture of gas and liquid, passes upwardly to the separator where the gas continues on to the compressor or absorber, as the case may be, while the liquid returns to the base of the coil. Any desired change in the back pressure, it will also be observed, can be obtained by merely changing the speed of the compressor or the temperature of the ab sorber because the proper liquid supply to the tank (5 or the bottom loop or loops of the coil, will be automatically maintained through the action of the float-controlled valve above described, and even though the condenser pressure may vary. The liquid flowing from the tank 3 may be led directly to the float controlled valve 5, if desired,

but it is preferred to pass it, as described above through the coil 18, which is within the separator casing so that it may be cooled thereby and in advance of its admission to the float tank. a

By further providing a. 'normally restricted pressure communication of definite capacity between the liquid reservoir 6 and the top of the separator, it is possible with the construction above'described to control or adjust the rate- 0f flow of the liquid through the freezing coil independently of the speed of thecompressor and in accord ance with the circumstances. The line 14 represents such a communication, 15 being a check-valve device opening toward the separator or suction line and loaded by a spring 16 which can be adjusted in an obvious manner, as by screwing the thrust-plug 17 in and out. The adjustment of the spring load on the valve provides for a more or less restricted escape of gas from the reservoir 6 to the separator whereby a predetermined difference of pressure can be automatically set up and maintained between the two, or, which is the same thing, between the inlet and exit of the cooling coil and by the adjustment thereof the pressure in the reservoir may be maintained at such a degree as to control the rate of liquid supply to the coil. for example so that gas of any degree of wetness may be caused to issue from the top loop thereof. I

Shut Off valves or other devices may be interposed in the connections above referred to where necessary or convenient, either for the purpose of disconnecting such parts or for superimposing additional regulation of liquid flow therethrough, and various other modifications of the system may also and obviously be resorted to without departing from the invention above described and pointed out in the following claims.

By the cooperation of the various expedients described, it will be observed that the operation of the freezing coil is made more or less automatic and independent of the varying demands thereupon without the necessity of manipulating the usual expansion valve. The amount of liquid refrigerant in the coil will vary with such demands but there will always be liquid present. Coil 18 serves to bring the temperature of the inflowing liquid ammonia to a degree corresponding to that obtaining in the system; whatever the operation of the compressor, etc, the liquid delivered to 6 is brought to a temperature corresponding to the temperatures in the coils. The flow of liquid through the coils is dependent on the pressure differential betw en 11 and 6, and this pressure differential can be automatically kept constant by valve 15 on the bypass 1 1 between 6 and 11. Whatever the amount of liquid refrigerant supplied to coil 10 and passing unconsuined therethrough, element 11 prevents its access to compressor 1.

I claim:

1. In a refrigerating apparatus, a refrigcrating C01] and suction line for removing expanded refrigerant therefrom, in combination with a liquid reservoir to supply the coil, means for admitting liquid refrigerant thereto at a higher pressure than the suction line pressure and an automatically operable pressure communication between the suction side of the said coil and the reservoir.

2. In a refrigerating apparatus, a liquid reservoir, means for supplying liquid refrigerant thereto, means for automatically controlling the supply of such liquid to the reservoir at a rate equivalent to the rate of outflow therefrom, and automatically acting independent means for controlling the pressure in the reservoir, in combination with a refrigerating coil supplied by the reservoir, and a suction line connected to the upper part of the coil and also connected to said automatically acting means.

3. In a refrigerating apparatus, a liquid reservoir means for supplying liquid refrigerant thereto and means for automatically admitting such liquid to the reservoir at a rate equivalent to the rate of outflow therefrom, a refrigerating coil supplied by the reservoir, a suction line connected to the coil, and a normally restricted gas communication between the suction line and reservoir, comprising valve parts suitably organized and tending to maintain a substantially constant difference of pressure therebetween.

4. In a refrigerating apparatus, aliquid reservoir and admission valve therefor, means controlling said valve for automaticall v admitting liquid refrierant to said reservoir at a rate equal to tie rate of outflow therefrom and automatically acting independent means for controlling the pres. sure in the reservoir, in combination with a refrigerating coil supplied with liquid from the reservoir, a gas and liquid separator distinct from said reservoir connected to the discharge of the coil, a gas suction line from the coil. connected with the separator and also connected to said automatically acting means, and a drain line leading from the separator to the reservoir.

5. In a refrigerating apparatus, a liquld reservoir having an admission valve with means for automatically controlling the same to admit liquid at a rate equal to the rate of outflow from the reservoir, in combination with a refrigerating coil supplied with liquid. from the reservoir, a as and liquid separator connected to the discharge of the coil, a suction line connected with the separator, a liquid drain line adapted to return liquid from the separator to the coil and a normally restricted pressure communication between the suction line and the reservoir adapted to maintain a substantially constant difference of pressure therel)(i3WQ0I1.

n. In a refrigerating apparatus, a refrigcrating coil, a liquid reservoir to supply, and a suction line to exhaust, the said coil, in combination with a normally restricted gas communication between the liquid reservoir and suction line, comprising parts ad]ustable to maintain different predetermined pressure differences therebetween.

7. In a refrigeratingapparatus, the combination with a refrigerating coil, a suction line for removing expanded refrigerant therefrom. such suction line comprising a separating chamber for liquid and vapor and a liquid reservoir for supplying the coil, of means for supplying liquid to the reservoir comprising a liquid conductor within such separating chamber and subjected to the temperature of the expanded refrigerant in the suction line and an auto matic valve operative to control the supply of such liquid to and maintain a predetermined level of the same in the reservoir.

8. In a refrigerating apparatus, the comhination with a refrigerating coil, a suction line for removing expanded refrigerant therefrom including a separator, and a liquid reservoir for supplying the coil, of

means for automatically maintaining a predetermined amount of liquid in the reservoir comprising a liquid supply line passing through the separator and an automatic valve controlling the admission of such liquid supply to the reservoir.

9. In a refrigerating apparatus, an expansion coil, means for maintaining a body of liquid under predetermined pressure connected to the inlet of said coil, means for separating liquid and gas connected to the outlet of said coil, means for returning separated liquid to the body and an independent pressure equalizing gas conduit connecting the separating means and the body, said conduit being provided with an automatic pressure. regulating device for controlling gas flow therethrough and fmaintaining a predetermined constant dif-. 'ference in pressure between the separating means and the body.

10. In a refrigerating apparatus, an expansion coil, means for maintaining a body A of liquid under predetermined pressure freely open to the inlet of said coil, means for maintaining a predetermined volume of liquid in said body independent of the pressure thereon, means for separating liquid and gas connected to the outlet of said coil, means for returning separated liquid to the body and an independent pressure equalizing gas conduit connecting the separating means and the body, said conduit being provided with an automatic pressure regulating device for controlling gas flow therethrough.

11. In a refrigerating apparatus, an expansion coil, means for maintaining a body of liquid under predetermined pressure freely open to the inlet of said coil, means for maintaining a predetermined volume of liquid in said body independent of the pres sure thereon, means for separating liquid and gas connected to the outlet of said coil, means for returning separated liquid to the body and an independent pressure equalizing gas conduit connecting the separating means and the body, said conduit containing a loaded check 'valve.

12. In a refrigerating apparatus, a refrigerating coil and suction line for removing expanding refrigerant therefrom, in combination with a liquid' reservoir to supply the coil, means for admitting liquid refrigerant thereto at a. higher pressure than the suction line pressure and an automatically operable pressure communication between the suction side of the said coil and the reservoir, said pressure communication having adjusting means whereby a predetermined difference of pressure can be antomatically maintained between the suction line and the reservoir.

13. In a refrigerating apparatus, a-refrigerating coil and a suction line for removing expanding refrigerant therefrom, in combination with a liquid reservoir to suppl the coil, means to admitting liquid rcl'rigerant to the reservoir at a higher pres sure than the suction line pressure, a precooler in communication with said reservoir and comprising a device in which the expanding refrigerant flows and in which the liquid under greater pressure is cooled, and a pressure connnunieation between said de vice and said reservoir whereby a difference in pressure can be maintained between the suction line and the reservoir.

M. In a refrigerating apparatus, means for supplying liquid retrigerant to a liquid reservoir and means for automatically admitting such liquid to the reservoir at a rate equivalent to the rate of outflow therefrom, a precooler for liquid admitted to said reservoir, :1 refrigerating coil supplied by the reservoir, a suction line connected to the eoil,and a normally restricted gas communication between the suetion line and reservoir, comprising valve parts suitably organized and tending to maintain a substantially constant difference of pressure therebetween.

In testimony whereof, I have signed this specification in the presence of two witnesses.

LOUIS K. DOELLING.

\Vitnesses MARGARET M. KLos, CLIFFORD II. KLes. 

